Lawn mowers having a clutch mechanism for clutch-controlling motive power transmission and having a control lever (clutch lever) for operating the clutch mechanism are in use. Lawn mowers of this kind are provided with a safety lock mechanism so that it is not possible to operate the control lever unintentionally.
A lawn mower having a clutch lever provided with a lock mechanism so that it is not possible to operate the clutch lever unless the lock mechanism is released is proposed for example in JP-UM-B-60-33785. This lawn mower will be described on the basis of FIG. 16 and FIG. 17.
As shown in FIG. 16, a lawn mower 200 has an engine 202 mounted on a cutter housing 201. A cutter blade 204 for cutting grass is connected to the engine 202 via a clutch mechanism 203. A handle 205 extends rearward from the cutter housing 201. A control lever (clutch lever) 206 for engaging and disengaging the clutch mechanism 203 is mounted on the handle 205 via a support bracket 208.
As shown in FIG. 17, the operating lever 206 has a lock mechanism 207 for locking its movement in an initial state. The lock mechanism 207 is made up of a lock piece 209, having its center pivotally attached to the support bracket 208, for locking the operating lever 206 with one end thereof, a tension spring 211 passing between the other end of this lock piece 209 and the support bracket 208; and a release lever 212, attached to the lock piece 209, for releasing the first end of the lock piece 209 from the support bracket 208. The lock mechanism 207 locks the operating lever 206 pivotally attached to the support bracket 208 in a predetermined state.
That is, the lawn mower 200 shown in FIG. 16, by having the operating lever (main operating part) 206 and the release lever (auxiliary operating part) 212, is of a type such that the clutch mechanism 203 is operated with two motions, and is constructed so that it is not possible to engage the clutch mechanism 203 and rotate the cutter blade 204 with one continuous movement of the operating lever 206.
However, in the lawn mower 200 of related art, the operating lever 206 is brought to an operable state with the release lever 212 and the clutch mechanism 203 is engaged with the operating lever 206, and this engaging operation of the clutch mechanism 203 depends on the sense of the operator. That is, sometimes a half-clutch state is continued for a long time when the operating lever 206 is moved. And as a result there has been the problem that the clutch mechanism 203 wears and the life of the clutch mechanism 203 becomes short.
The lock piece 209 is released by pushing the release lever 212. When engaging the clutch mechanism 203, it is necessary to operate the operating lever 206 so as to shift it toward the handle 205 while pushing the release lever 212. Consequently, it sometimes happens that an attempt is made to shift the operating lever 206 with the release lever 212 uncertainly pushed, there is uncertainty in the engagement control of the clutch mechanism 203, and there has been the shortcoming that the controllability of the engagement control of the clutch mechanism 203 is poor.
Accordingly, a lawn mower has been needed with which, as well as it being possible to control the clutch mechanism with two motions, dependence of the engagement operation of the clutch mechanism on the sense of the operator is avoided, and it is possible to make the clutch engagement control certain. That is, a lawn mower has been awaited with which it is possible to keep the engagement operation of the clutch mechanism to a fixed timing and it is possible to carry out a two-motion control operation.